TY - JOUR
T1 - Reversing gene expression in cardiovascular target organs following chronic depression of the paraventricular nucleus of hypothalamus and rostral ventrolateral medulla in spontaneous hypertensive rats
AU - Geraldes, Vera
AU - Goncalves-Rosa, Nataniel
AU - Tavares, Cristiano
AU - Paton, Julian F.R.
AU - Rocha, Isabel
N1 - Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/9/1
Y1 - 2016/9/1
N2 - Background Chronic overexpression of an inwardly rectifying potassium channel (hKir2.1) in the paraventricular nucleus of the hypothalamus (PVN) and in the rostral ventrolateral medulla (RVLM) to suppress neuronal excitability, resulted in a long term decrease of blood pressure and sympathetic output in spontaneously hypertensive rats (SHR). Objective Evaluate gene expression in end-organs of SHR after a chronic overexpression of hKir2.1 channels in either the PVN or RVLM. Methods mRNA levels of 16 genes known to be involved with blood pressure regulation were evaluated using RT-PCR in tissues from the heart, common carotid artery and kidney of SHR submitted to chronic depression of PVN and RVLM excitability using a lentiviral vector (LVhKir2.1). Results In SHR hearts in which either the PVN or RVLM were injected with LVhKir2.1, there was a downregulation of angiotensin II receptor 1b (AT1), ATPase, Ca2+-transporter, troponin T2 and tropomyosin2 (only in RVLM) relative to the sham group. In the kidney of SHR with LVhKir2.1 injections in PVN and RVLM, angiotensinogen, angiotensin II receptor2 (AT2) and endothelin1 were all upregulated compared to sham. In the carotid artery, endothelin2, endothelin receptor A and B were up-regulated following LVhKir2.1 in to either the PVN or RVLM relative to sham. Conclusion Chronic overexpression of hKir2.1 channels in PVN and RVLM, promoted a BP decrease with up-regulation of angiotensinogen and AT2 genes expression in the kidney and down-regulation of AT1 in the heart of SHR. Thus, we demonstrate the potential efficacy of central manipulation to protect against end-organ damage in essential hypertension.
AB - Background Chronic overexpression of an inwardly rectifying potassium channel (hKir2.1) in the paraventricular nucleus of the hypothalamus (PVN) and in the rostral ventrolateral medulla (RVLM) to suppress neuronal excitability, resulted in a long term decrease of blood pressure and sympathetic output in spontaneously hypertensive rats (SHR). Objective Evaluate gene expression in end-organs of SHR after a chronic overexpression of hKir2.1 channels in either the PVN or RVLM. Methods mRNA levels of 16 genes known to be involved with blood pressure regulation were evaluated using RT-PCR in tissues from the heart, common carotid artery and kidney of SHR submitted to chronic depression of PVN and RVLM excitability using a lentiviral vector (LVhKir2.1). Results In SHR hearts in which either the PVN or RVLM were injected with LVhKir2.1, there was a downregulation of angiotensin II receptor 1b (AT1), ATPase, Ca2+-transporter, troponin T2 and tropomyosin2 (only in RVLM) relative to the sham group. In the kidney of SHR with LVhKir2.1 injections in PVN and RVLM, angiotensinogen, angiotensin II receptor2 (AT2) and endothelin1 were all upregulated compared to sham. In the carotid artery, endothelin2, endothelin receptor A and B were up-regulated following LVhKir2.1 in to either the PVN or RVLM relative to sham. Conclusion Chronic overexpression of hKir2.1 channels in PVN and RVLM, promoted a BP decrease with up-regulation of angiotensinogen and AT2 genes expression in the kidney and down-regulation of AT1 in the heart of SHR. Thus, we demonstrate the potential efficacy of central manipulation to protect against end-organ damage in essential hypertension.
KW - Common carotid artery
KW - Heart
KW - Hypertension
KW - Kidney
KW - Sympathetic nervous system
KW - mRNA
UR - http://www.scopus.com/inward/record.url?scp=84973343121&partnerID=8YFLogxK
U2 - 10.1016/j.brainres.2016.05.041
DO - 10.1016/j.brainres.2016.05.041
M3 - Article
C2 - 27238462
AN - SCOPUS:84973343121
SN - 0006-8993
VL - 1646
SP - 109
EP - 115
JO - Brain Research
JF - Brain Research
ER -